optional_depends X11-LIBS \
                 "--with-x" "--without-x" \
                 "For GUI support" &&

optional_depends libusb \
                 "--enable-libusb" "--disable-libusb" \
                 "For libusb support" &&

optional_depends bluez-libs \
                 "--enable-bluetooth" "--disable-bluetooth" \
                 "For bluetooth support" &&

optional_depends libical \
                 "--enable-libical" "--disable-libical" \
                 "For iCal support" &&

if is_depends_enabled $SPELL X11-LIBS; then
  depends gtk+2
fi
